Spending on mobile advertising in the U.K. more than doubled in 2010, reaching a total of £83 million ($135 million) worth of investment, according to the IAB U.K.’s annual mobile ad spend report.

The survey, conducted in conjunction with PricewaterhouseCoopers, found that advertiser spend on the bourgeoning medium grew 116 percent on a year-over-year basis, representing considerable acceleration versus the 32 percent growth the research recorded in 2009.

The IAB attributed the increase to the continued rise in smartphone adoption, but also to a change in consumer behavior. Users are accessing more online content via their mobile devices than ever before, spending 45 percent longer doing so in 2010 than the previous year, according to data from the GSM Association.

In addition to that increased consumer engagement, the types of advertisers now investing in mobile ads has also become far more diverse, the research suggested, with advertisers in the finance, automotive, and consumer packaged goods verticals spending far more substantially than they did in 2009. As a result, the entertainment and media vertical accounted for a far smaller overall share of spend in 2010, having accounted for over 60 percent in 2009.

Top U.K. Mobile Advertising Verticals by Ad spend, 2010.

Vertical

Share of Ad Spend (%)

2009

2010

Entertainment & Media

61.5

32.9

Finance

8.1

18.6

Telecoms

14.7

14.3

Consumer Goods

3.2

11.8

Automotive

2.5

6.5

Source: IAB U.K., PwC

As with the desktop Web, spending on search platforms dominated mobile ad spend in 2010, accounting for a 66 percent share overall. Display accounted for a 29 percent share, meanwhile, while other formats such as pre and post-roll ads and SMS advertising accounted for five percent of spend.